1. Field of the Invention
The invention relates generally to electromagnetically driven valves. More particularly, the invention relates to pivot-type electromagnetically driven valves that are used in internal combustion engines and are driven by electromagnetic force and elastic force.
2. Description of the Related Art
Electromagnetically driven valves have been disclosed, for example, in U.S. Pat. No. 6,467,441.
In U.S. Pat. No. 6,467,441, a pivot-type electromagnetically driven valve having a fulcrum on a disc (armature) is disclosed. When two conventional flap type electromagnetically driven valves are placed adjacent to one another and operated, the number of drive circuits increases, as does the cost and the space required for installation. Also, the electromagnetic interference between the adjacent electromagnetically driven valves reduces the electromagnetic force and increases the amount of electric power that is consumed. Also, if an attempt is made to operate two driven valves by means of one electromagnetically driven valve, the difference in the tappet clearance of the two driven valves gives rise to tappet noise.